Binary superimposed gratings for tunable DBR lasers

Summary form only given. Summary form only given. Both sampled gratings (SG) and superstructure gratings (SSG) used in tunable lasers previously rely in periodical modulation of a uniform grating, and it is the modulation period which determines the reflectance peak positions. In this paper we suggest a new DBR structure based on binary superimposed gratings (BSG), that is easier to implement and has a built-in freedom in adjusting the individual positions and amplitudes of the reflectance spectrum peaks.